Brake



July 23, 1935. A. c. CHAMBERS BRAKE Filed Oct. 16, 1930 IN VEN TOR. HALE/v [HF/155 15 able area 'ofthe friction means will New J l 23, 9.

v Q Allen 0, Chambers, South BendixwBrake Company, corporation of Illinois d v H October is, 1930, Serial P v 140mm. ((1188-78) Application This'invention relates to brakes and is illusas embodied in an internal expanding brake tor automobile. An 'ObjCCt of the invention is to provide a novel anchorage tor the brake which will be actuated by the torque of the braketo intensify the brake applying force, thatis, to'give a self-energizing eilect.

:Preierably't'his novel anchorge is" arranged to be operated by the torque ofthe'brake to force against thefrotatin'g brake drum two parts of the brake friction means which are spaced some'distance apart'so that a consider- I hemmed against the drum with great power by'force derlved from the braking torque. In one arrangement which is illustrated in the drawing, the brake iriction device anchors on a iever'agemeans which has two parts engaging portions oi the friction device on opposite sides of the anchorage and which are operated by the torque of the brake to force the corresponding parts of the iriction device radially against the drum." I prefer to usetwo' leverage devices in the brake anchorage, one of which is effective when the drum is tuming monedirection and the other of which is effective when the drum is turning in the opposite direction. I

Various other objects and features oithe invention, including novel and desirable structural details, will be apparent iro'mjthe following description of the illustrative embodiment shown in the accompanying drawing, in which:

Figure l, is a vertical section through the brake f its inside the'head" or the rake ar a he the novelbrake friction means i vadam-1,5? L "11.1

gureiz is. a.partial'section"onjthe iine 20f h n l o topfiumzn I lf lgiil-e 3 is a p rtial section on the line 3-H:- Figure '2' and showing one oi the leverage devices of the brake anchorage; and V Figure 4 is a view corresponding to part oi. Figure 3, but showing a modified formoi leverage device.

The illustrated brake includes a rotatable-drum II at the open side oi! which is a suitable support such as a backing plate arranged the friction means or the brake, shownior purposes oi! illustration .as a flexible expansible band ll laced with the usual brake lining and operated by means such as a hydraulic cylinder and pair of pistons it against the resistance of the usual return spring l8.

According to the present invention, f the torque brake acti clockwise in Figure 1 the i2 and within which is,

Bend, assignor to South Bend, Ind., a

of the friction means "is taken 'by-a novel anchorage illustrated as including a pair of opp sitely arranged-similar bellcrank levers 20 and 22 arranged one behind the other. crumed on 'aiix'edpost 24 carried by the backing 5 The downwardly extending arms oi the plate.

and both fullevers 2nand- 22are embraced by brackets 25 on the band I so that the torque oi.

the band. when the brake is-applied is transmitted to these downwardly extending arms and thence to the anchor post 24.- The other arms oi-thebellcrank levers engage the'inner lever 20 engaging it to 24 in'Figuresl and 3 an'd face of theiband'll, the endo! the leit oi the anchor post the end 01' the lever 22 engaging it to the right of the anchor post 24.

It will be' seen that when the drum is turning hell crank lever 2i]v is relatively ineffective as an anchorage-while'the bell crank lever 22 forms the effective brake anchor and rocks about the anchor post 24 to urge the right hand portion of the band I l radially outward against the drum. the band is permitted by of the brackets 25 with the lower levers 20 and 22. It clockwise, the lever 22 This radial movement oi! the sliding engagement portions 01' the the drum is turning counteris comparatively ineffective as an anchorage and'the lever 20 is operated to transmit the torque of the brake to the post 24 and also to shift the leithand portion oi the band radially outward against the drum.

shift against the device opposite the end In order also to portion of the friction calm the of lever 22 or 20, whichever one is effective, I pronounces-en me a relatively large'bpening um vide a pair of auxiliary levers 26 and 28 operatively enga'sedrespectively'by and zzgrna 'flilcrumed-"rspectively on. :a post 31] I v I "backing 'plateand a mounted on thebackiiis' plate andpassing through the bell crank .lever' 22 so'that'it does not interfere with the the bell crank-levers 20 post-Maisomovement or the bell "crank' ever 22. Return springs 'iil are preferably tensioned between; the

our levers 20, 22, 28 and 28 and the inner face of the band and urge the entire lever system toward its released position.

It will be seen that whenthe lever 20 is effective anchorage and is urging the leithand porit will also operate the lever 26 to. urge the righthand portion of the band radially outward; similarly,

an anchorage and is urging lever 22 is effective as when the the righthand portion of the bandoutward, it operates lever 28 to urge the bandoutward. Thus, 7 drum. rotation, the entire lower the lefthand portion or in either direction of:

portion. oi the band i 4 is urged with great force outward against the drum with a self-energizing effect to increase the braking power.

As shown in Figure 4, instead of the cam surfaces by which the levers engage, they may be connected by intermeshing rack teeth.

While one illustrative embodiment of the invention has been described in detail, it is not my intention to limit its scope to that particular embodiment or otherwise than by the terms of the appended claims.

I claim:

1. A brake comprising a rotatable drum and a friction device engageable with the drum, in com;- bination with anchorage means'for the friction device having a movable part engaged by the] friction device and taking the torque thereof and which is shifted upon application of the brake to apply radial force to the friction device simultaneously at spaced points on opposite sides of the anchorage. I

2. A brake comprising .a rotatable drum and a friction device engageable with the drum, in combination with anchorage meansfor the friction device including apart which takes the torque from the friction device and which is shifted by saidf-torque and spaced parts simultaneously operatedby the shifting thereof to apply force in a radial" direction against spaced portions of the friction device on opposite sidesofthe anchorage means. +3. Abrake comprising a rotatable drum and a -friction device engageable therewith, in combination'with anchorage means vtaking the torque of the friction device and including two .lever devices arranged side by side, one of which is .operated by the torque-of the brake when applied with the drum turning in one direction to force the friction device radially against the drum and the other of which is operatedby the torque of the brake when the drum is turning inthe other direction to force the friction device radially against the drum. v

4. A brake anchorage comprising a fixed pivot,

a bell crank lever mounted on said fixed pivot and having one arm adapted to serve as the anchor for a brakefriction device and the other arm arranged to engage the friction device to urge it radially, in combination with another separately fulcrumed lever engaged and operated by the bell crank lever to force another portion of the friction device radially.

5. A brake comprising a drum and a friction device, in combination with an anchorage for the friction device including one lever forcing spaced portions of the friction device against the drum when the drum is turning in one direction and another lever forcing spaced portions of the friction device against the drum when the drum is turning in the other direction.

6. A brake comprising a drum and a friction device, in combination with an anchorage for the friction device including means forcing spaced portions of the friction device againstthedmin when the drum is turning in one direction and another means forcing the same spaced portions of the friction device against the drum when the drum is turning in the other direction.

7. A brake comprising a drum and a friction device, in combination with two devices arranged 'side by side and alternatively operable to force the friction device against the drum and each of which devices acts on circumferentialiy spaced' portions of the friction device. v

8. A brake comprising friction means, a pair of spaced pivots arranged adiacent'the friction means, and two lever devices arranged side by side and fulcrumed on said pivots and acting on said-means.,.;eachf*lever device comprising two inter-engaging parts fulcrumed respectively on.

said pivots; i

.2 9. Abrakecomprising friction means, a pair of spaced pivots arranged adjacent the friction means and serving as anchorage means to take the braking torque, and two lever devices-arrangedside byside and fulcrumed said pivots and operated by the b akingltorqiie the applicationof the brake.

10. A brake c mprisingfriction 'meaiis, [pair of spaced pivots arranged adjacent the friction means, and two pairs of; -levers m m anv t the n w; 1 ranged; s de by h '0h.' One P a PP YmKL Q-Z o a. plurality of o friction means when .the br'ak n i nisn ii ee sa ss-- plying action on apluralityof parts er; the fric ean sheaths. b k's j in the otherdirection. 11. A brakecomprising'frictionmeans, apaii' of spaced pivots' arranged adjacent the friction means, and. two .of' interconnected jlevers fulcrumed on said pivots,,.'the.pairs being "arranged side by side thereon and alternativelyoperable to have an app action on a'plurality of parts of the friction m'eans.'. f

12. A brakeanchorage comprising two pairs .of interconnected parts, each pair having an anchor portion engageablewith friction means and each having. afplu'rality. of portion: simultaneously given' a brake-applying movement by thrust on its anchor portion.

13. A brake anchorage comprising two pairsof interconnected parts arranged side by side, each pair having an anchor portion and a plurality of brake-applying portions." j

'14. A brake device comprising a bell crank lever having a torque-receiving portion and an applying portion operated by thrust on' the torque-receiving portion, and a separately-fulcrumed lever also having an applying portion and 'operatively engaged by the bell cranlr'lever to be operated by thrust on said torque-receiving portion.

, 'C. CHAMBERS. 

